Verifying Accuracy; Overview Of Meter Accuracy; Accuracy Test Requirements - Siemens 9410 Series User Manual

9410 series

Verifying accuracy

Overview of meter accuracy

Accuracy test requirements

Signal and power source
Control equipment
184
All meters are tested and verified at the factory in accordance with International
Electrotechnical Commission (IEC) and American National Standards Institute (ANSI)
standards.
Your digital power meter typically does not require re-calibration. However, in some
installations a final accuracy verification of the meters is required, especially if the
meters will be used for revenue or billing applications.
The most common method for testing meter accuracy is to apply test voltages and
currents from a stable power source and compare the meter's readings with readings
from a reference device or energy standard.
The meter maintains its accuracy during voltage and current signal source variations
but its energy pulsing output needs a stable test signal to help produce accurate test
pulses. The meter's energy pulsing mechanism needs approximately 10 seconds to
stabilize after every source adjustment.
The meter must be connected to control power in order to conduct accuracy
verification testing. Refer to your meter's installation documentation for power supply
specifications.
HAZARD OF ELECTRIC SHOCK, EXPLOSION, OR ARC FLASH
Failure to follow these instructions will result in death or serious injury.
Verify the device's power source meets the specifications for your device's power
supply.
Control equipment is required for counting and timing the pulse outputs from an energy
pulsing LED or digital output.
• Most standard test benches have an arm equipped with optical sensors to detect
LED pulses (the photodiode circuitry converts detected light into a voltage signal).
• The reference device or energy standard typically has digital inputs that can
detect and count pulses coming from an external source (i.e., the meter's digital
output).
NOTE: The optical sensors on the test bench can be disrupted by strong sources
of ambient light (such as camera flashes, florescent tubes, sunlight reflections,
floodlights, etc.). This can cause test errors. Use a hood, if necessary, to block out
ambient light.
DANGER
Verifying accuracy
7EN05-0336-03